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It turns out the old saying about sticks and stones breaking bones but words never hurting is bunk.

According to research newly published in the peer-reviewed Early Childhood Research Quarterly, emotional bullying in the preschool years hurts quite a lot. When a child both bullies and gets bullied, the findings are especially clear: Depression symptoms begin to appear as early as age 3. Depression in early childhood increases the risk of depression in later childhood, which predicts depression in adolescence.

Bullying by young children is “very obvious,” said Tracy Vaillancourt, a professor of child psychology at the University of Ottawa and co-author of the study. “They’re not very good at it but it’s still very effective.”

Two- to 3-year-old preschool students engage in emotional bullying by refusing to let certain classmates sit by them, threatening to withhold their friendship from others, blocking classmates out by turning their backs or even just closing their eyes and covering their ears. Stating that so-and-so “can’t come to my birthday party” is and especially common weapon, Vaillancourt said.

Physical aggression is also common at this age (65 percent of children use it regularly, Vallaincourt said) and occasional displays of either type of aggression are pretty normal. But for children who frequently engage in emotional bullying and who also frequently find themselves on the receiving end of such tactics, the results can be serious.

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Among the 198 mostly white, middle class Canadian preschool students studied, bullying bullies were the most likely to show symptoms of early childhood depression.

“You can garner so much more support if someone thumps you on the head, because everyone sees it. But if someone says something to you behind the back of the teacher, you could really suffer in silence for a long time.”

“Kids who are depressed are actually pretty easy to pick out too,” Vaillancourt said of preschool-age students. Two- and 3-year-olds “are inherently little narcissists. They think they’re amazing — the fastest runners, the funniest. So it would be atypical for them to say they hate themselves or be down on themselves.”

Vaillancourt said depressed toddlers also have negative themes in their play, like telling a toy it’s “bad,” and they often have sleep, appetite and activity disturbances like older depressed people. They may sleep a lot and could move really slowly from one activity to the next. Changes from normal behavior, like a generally happy kid who is suddenly saying negative things about him or herself, are other indicators that a young child may be suffering from depression, Vaillancourt said.

All of the students observed for this study attended publicly funded preschools in Ontario, Canada, which served 2- and 3-year-olds and were rated high quality. (Most regions of the U.S. do not offer any public preschool option for children as young as 2.) Teachers at public Canadian preschools must be highly educated and well trained in early childhood development. That fact may have actually dampened the effect of bullying, Vaillancourt said. Students at a lower quality school receiving less support from teachers may engage in more bullying and be more likely to get bullied, leaving them at even higher risk of developing clinical depression.

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This study did not examine conditions in children’s homes. While the current understanding of childhood depression assumes that a child’s home environment has a clear impact on a child’s condition, researchers have said peer relationships among young children should also be studied more carefully. The introduction to this study states that it was undertaken in part as a response to that call.

Finally, the study looked at gender to determine if it had any effect on how children reacted to both physical and emotional aggression. In short, they found no significant differences between boys and girls, though girls were slightly more likely to engage in emotional bullying. This may be due, in part, to their more developed social skills. Prior research from the U.S. has linked the ability to be an emotional bully in preschool to having more friends and better language skills.

Teachers and parents should watch carefully for signs of emotional bullying and depression, Vaillancourt said, because though they are fairly clear they can get missed in the hubbub of daily life with a 2- or 3-year-old.

“You can garner so much more support if someone thumps you on the head, because everyone sees it,” she said. “But if someone says something to you behind the back of the teacher, you could really suffer in silence for a long time.”

This story about early education was produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education. Sign up for the Hechinger newsletter.

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